Creamy Watercress Dressing (Yeild 2 cups):
Roughly chop 3 bunches of watercress (reserve 1), place it in a medium saucepan and add buttermilk so that it is just covered. Warm the buttermilk over low heat for 5 minutes and remove from heat. Let cool at room temperature for up to 1 hour. This will steep the watercress and allow its flavor to be extracted. In a food processor, puree the buttermilk and watercress mixture, along with the reserved buttermilk and watercress. Add salt and pepper, Fromage d'Auvergne, vinegar, 1 bunch watercress and process until smooth. Taste and adjust seasonings.
Toss arugula, dill and red onions in Creamy Watercress Dressing until coated. Place in center of the plate, lay string beans along the edge and set the hard-boiled egg white atop the greens. Fill the center of the egg white with parsley pesto. Garnish with crumbled egg yolks.